The soup was cold, but it was ______ an excellent meal.

 His face looks brown because he works ____ all day.

____ to the surprise of the teachers, the naughty boy turned out to be the person who saved the dying girl. 

The incomes of skilled workers went up. ______， unskilled workers saw their earnings fall.

 Nature reserves are very important for preserving many animals and plants, which would _______ run the risk of becoming extinct.